1. Field of the Invention
This invention relates to a method and apparatus for controlling an internal combustion engine.
2. Description of the Prior Art
In a conventional electronic method of controlling an internal combustion engine, a method is employed using a reference pulse sensor for generating a reference pulse at predetermined crank angle periods in synchronization with the rotation of a crank shaft, and a crank angle sensor for generating a crank angle pulse at a fixed crank angle period shorter than the period of the reference pulse. Fuel injection timing and ignition timing are electronically controlled by using the reference pulse and the crank angle pulse.
However, in the conventional control method, when the reference pulse is not generated because of a fault or abnormality in the reference pulse sensor, e.g., the breakage thereof, control of the fuel injection timing and the ignition timing is rendered impossible, and as a result it is hard to control the engine.